1. Field of the Invention
The present invention relates to an optical disk cartridge for DVD-RAMs (digital versatile disk RAMs), and more particularly, relates to an optical disk cartridge suitable for use with 80 mm disks.
2. Description of the Related Art
Some optical disks, such as some CDs and DVDs, are writable. Such writable optical disks are generally used while being accommodated in an optical disk cartridge. In addition, the optical disk cartridge generally includes a write-protection discrimination mechanism for determining whether or not writing of information on the optical disk is prohibited.
A conventional optical disk cartridge including a discrimination mechanism will now be described with reference to FIG. 30.
A casing 21 is formed with an accommodating section 21a for slidably accommodating an operation piece 22.
Elongated holes 21b and 21c are formed opposite each other in the top and bottom faces, respectively of the accommodating section 21a. The elongated hole 21b is an operating hole for slidably operating the operation piece 22, and the elongated hole 21c is a discrimination hole in which a detection pin 23 disposed in a disk driving apparatus (not shown) can be inserted so as to determine whether or not writing of information on the disk is prohibited.
The arrangement of the operation piece 22 is such that a top face 22a enters slightly (in the thickness direction thereof) inward from the top face of the casing 21 without projecting to the top face of the casing 21, and a projection 22b on the bottom face is fitted into the elongated hole 21c so as to be substantially flush with the bottom face of the casing 21.
When an operation tool (not shown) is inserted into the elongated hole 21b to slide the operation piece 22 to the left side in the figure, the region of the elongated hole 21c is closed, whereby the insertion of the detection pin 23 into the elongated hole 21c is blocked, and it is thereby detected that writing of information on the disk is prohibited.
The top face 22a of the operation piece 22 is recessed slightly inward from the top face of the casing 21 in order to prohibit accidental operation of the discrimination mechanism by making the operation of the operation piece 22 difficult.
However, since the projection 22b is fitted into the elongated hole 21c and an end of the projection 22b is substantially flush with the bottom face of the casing 21, the operation piece 22 may be easily operated from the bottom face of the casing 21.
Therefore, the conventional disk cartridge cannot securely prohibit the accidental operation of the discrimination mechanism.
Accordingly, it is an object of the present invention to provide an optical disk cartridge capable of securely prohibiting accidental operation of a write-protection discrimination mechanism.
In accordance with the present invention, there is provided an optical disk cartridge including: a casing accommodating an optical disk therein and having an accommodating section formed by a pair of top and bottom walls; and an operation part slidably accommodated in the accommodating section of the casing; wherein an operating slot for slidably moving the operation part is formed in one of the walls, and a surface of the operation part is disposed inward from a surface of one of the walls; and wherein the other of the walls is provided with a closing part for closing an area opposing the operating hole, leaving a discrimination hole for inserting a detection pin so that the discrimination hole is opened and closed by the operation part.
In the optical disk cartridge of the present invention, one of the walls may be provided with the operation slot at one of left and right positions across the widthwise central part of the casing, and may be provided with the discrimination hole at the other of the positions; and the other of the walls may be provided with the discrimination hole at a position opposing the operating slot provided in one of the walls, and may be provided with the operating slot at a position opposing the discrimination hole provided in one of the walls.
The optical disk cartridge of the present invention may further include a holder capable of insertion and removal of a disk into and from the accommodating section. The holder may be accommodated in the accommodating section of the casing, the holder may be provided with a receiving part for receiving the operation part, and the operation part received in the receiving part may be insertable and removable into and from the accommodating section in accordance with insertion and removal of the holder.
In addition, the holder may be provided with a guide part around the receiving part for guiding a sliding movement of the operation part.
In the optical disk cartridge of the present invention, the operation part may be formed with an operation tool-insertion hole adjacent to the operation slot for receiving an operation tool.
In the optical disk cartridge of the present invention, the discrimination hole may be for determining whether or not writing of information on the disk is allowed.